Relay with lock-in and manual reset

ABSTRACT

A relay is comprised of a terminal block with a coil, an armature mounted for cooperation with the coil, at least one pole operated by the armature, and the improvement of a lock-in and manual reset mechanism. The mechanism includes a reset member with an attached stud. The stud engages and holds or locks the armature in a fixed position whenever the coil is energized. The reset member is biased between the terminal block and the cover of the relay and may be manually displaced against the biasing force to release or unlock the armature.

United States Patent 3,396,352 8/1968 Wilson 335/170 Primary Examiner-Harold Broome Attorney-Molinare, Allegretti, Newitt & Witcoff ABSTRACT: A relay is comprised of a terminal block with a coil, an armature mounted for cooperation with the coil, at

least one pole operated by the armature, and the improvement RELAY WITH LOCK-IN AND MANUAL RESET BACKGROUND OF THE INVENTION This invention relates to an improved lock-in mechanism reset device for an electrical relay.

Overloading locking devices, which are adapted to retain a relay in a fixed configuration subsequent to overloading, are known. Typically, a bracket is attached to the terminal block of the relay and a leaf spring of some sort is attached to the bracket. Whenever the armature of the relay is energized, the leaf spring, which is normally resting against the surface of the armature, snaps to a second or locking position for the armature. To free the armature, a manual reset button may be pro vided to engage and bias the leaf spring and thereby free the annature so that it can consume its normal position. The manual reset button is most often attached to a separate bracket affixed to the relay terminal block.

Such lock-in and manual reset arrangements are quite useful and adequately serve their purpose. However, in the past, it has been extremely difficult to incorporate such a manual reset device into small relays. The additional components required for the relay lock-in mechanism and the difficulty in maintaining proper tolerances and spring settings, and high manufacturing costs are some of the reasons such mechanisms are not often found in small relays.

SUMMARY OF THE INVENTION In a principal aspect, the present invention comprises the improvement in a relay of the type having a coil and armature mounted on a terminal block with a relay cover of a lock-in and manual reset mechanism. The mechanism includes a reset member mounted between the terminal block and cover and biased for movement substantially in a direction perpendicular to the direction of armature travel. The reset member includes stud means adapted to engage the armature and lock it in a fixed position whenever the coil has been energized.

It is an object of the present invention to provide an improved relay lock-in and manual reset mechanism.

It is a further object of the present invention to provide a lock-in and manual reset mechanism which may be incorporated as part of presently manufactured relays.

Still another object of the present invention is to provide an improved lock-in and manual reset mechanism for relatively small relays.

One further object of the present invention is to provide an improved relay lock-in and manual reset mechanism which is economical to manufacture, easy to fabricate and which is highly reliable.

These and other objects, advantages and features of the present invention will be set forth in greater detail in the description which follows:

BRIEF DESCRIPTION OF THE DRAWINGS In the detailed description which follows reference will be made to the drawing comprised of the following FIGS.

FIG. 1 is a side cross-sectional view of the improved relay of the present invention;

FIG. 2 is a front cross-sectional view of the improved relay of the present invention taken substantially along the line 2-2 of FIG. 1; and

FIG. 3 is a bottom plan view of the improved relay of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the FIGS. the relay of the present invention is mounted on a terminal block 10. A cover 12 cooperates with V the armature 20 outwardly from the vcoil 14 about a pivot point 26.

A two-pole contact block 28 is attached to the armature 20. The block 28 is made of an electrical insulating material. The contact block 28 includes first and second contact poles 30 and 32, respectively. The poles 30 and 32 move coextensively with the armature 20. Affixed at the ends of the poles 30 and 32 are doubled-headed contacts as at 34. THe contacts as at 34 are adapted to engage contacts as at 36 and 38 on terminal lugs 40 and 42. respectively, mounted in the block 10. Coil lead lugs 44 and 46 are also provided in the terminal block 10. Lugs 48 and 50 mounted in terminal block 10 include leads as at 52 and 54, respectively, connected to the first pole 30 and second pole 32, respectively.

What has heretofore been described as a typical small, double-pole double throw relay. The improved mechanical lock and manual reset mechanism of the present invention will now be described. The mechanism of the invention includes a reset member 56 extending longitudinally between the block 10 and cover 12. The reset member 56 is comprised of three parallel, vertical runs or sections, the upper run 58, the middle or stud receiving run 60 and bifurcated lower or parallel guide runs 62 and 64. The reset member 56 is fabricated from a light gauge metal. Each of the three runs 58, 60 and 62, 64 are interconnected by horizontal runs. Thus, a lower connecting horizontal run 66 connects runs 62, 64 with run 60.

A biasing spring 68 is positioned between the block 10 and the run 66 to thereby bias the reset member 56 upwardly toward the top of the cover 12. The reset member 56 is movable only in the vertical direction which is substantially perpendicular to the direction of travel of the armature 20.

Attached to the middle run 60 through an opening provided therein is a stud 70. The stud 70 is preferably fashioned from a nonconduction plastic material such as DELRIN, a trademark of DuPont. The plastic stud 70 may thus be snapped in an opening provided in the middle run 60.

The stud 70 includes a first armature-engaging surface 72 and a second armature-engaging surface 74 substantially parallel to the first surface 72. When the armature 20 is in a position wherein the coil 14 has not been energized, the first surface 72 engages the lower end of the armature 20. THe first surface 72 is biased against the armature by the spring 68 acting on reset member 56.

When the coil 4 is energized, the armature 20 swings inwardly to the phantom position shown in FIG. 1 and the reset member 56 and attached stud 70 rise vertically so that the second armature-engaging surface 74 abuts the armature 20 as shown by the phantom position in FOG. 1. Subsequently, when the coil 14 is deenergized, the armature 20 and thus the poles 30 and 32 are maintained in the locked position by the stud 70.

A manual reset button 76 is attached to the upper end of the upper run 58 which extends through an opening 78 provided in the cover 12. By depressing the button 76 against the force of the spring 68, the armature 20 is permitted to return to its deenergized position for the coil 14. A portion 80 of the upper run 58 may be color-coated to provide a visual indication that the relay is in the locked position.

In the embodiment shown, a four-pole, double throw switch has been converted to a two-pole double throw switch with the improved lock and reset mechanism by substitution of the reset member in the position formally occupied by two of the four-pole switch. With such a construction, the lower run 62, 64 utilizes the openings in the block 10 formerly used for lugs associated with the other two poles mounted on the annature. Thus, it can be appreciated that the feature of the present invention can be incorporated with four-pole switches by a minimum of modification.

What is claimed is:

1. In a relay having a terminal block with a coil having an end mounted thereon, a pivotally mounted armature parallel to the end of said coil normally biased about an armature pivot axis away from said coil and movable toward said coil end whenever current is passed through said coil, at least one tion by preventing biased movement of said armature movable pole operated in response to armature movement, about said armature pivot axis and simultaneously the improvement of an armature position lock and reset preventing movement of said reset member in said first mechanism comprising, in combination: sense, and said reset member including integral manually a longitudinal reset member positioned in a plane substan- 5 operably means for translating said reset member against tially parallel with said armature and translatable in said Said biasing means parallel plane in a direction substantially perpendicular to The improved y of claim 1 wherein Said said armature pivot axis, said reset member including 8 8 'f also mcludes f means w p move biasing means f continuously biasing said member in a ment of said reset member in said first sense when said armafirst sense, said reset member also including armature-en- 10 is mocked Position gaging means for holding said armature in a locked posi- 

1. In a relay having a terminal block with a coil having an end mounted thereon, a pivotally mounted armature parallel to the end of said coil normally biased about an armature pivot axis away from said coil and movable toward said coil end whenever current is passed through said coil, at least one movable pole operated in response to armature movement, the improvement of an armature position lock and reset mechanism comprising, in combination: a longitudinal reset member positioned in a plane substantially parallel with said armature and translatable in said parallel plane in a direction substantially perpendicular to said armature pivot axis, said reset member including biasing means for continuously biasing said member in a first sense, said reset member also including armature-engaging means for holding said armature in a locked position by preventing biased movement of said armature about said armature pivot axis and simultaneously preventing movement of said reset member in said first sense, and said reset member including integral manually operably means for translating said reset member against said biasing means.
 2. The improved relay of claim 1 wherein said armature-engaging means also includes second means to prevent movement of said reset member in said first sense when said armature is in an unlocked position. 